# Standard Form Short Questions (Question 1 - 5)

Question 1:
Round off each of the following numbers to the number of significant figures indicated in brackets.
(a) 80616 (3 s. f.)
(b) 60932 (3 s. f.)
(c) 0.4783 (2 s. f.)
(d) 3.047 (3 s. f.)
(e) 0.00567 (2 s. f.)
(f) 0.05086 (3 s. f.)

Solution:
(a) 80600
(b) 60900
(c) 0.48
(d) 3.05
(e) 0.0057
(f) 0.0509

Question 2:
Express each of the following as a single numbers.
(a) 8.565 × 10-5
(b) 1.304 × 105
(c) 6.754 × 10-6
(d) 1.0352 × 104

Solution:
(a) 0.00008565
(b) 130400
(c) 0.000006754
(d) 10352

Question 3:
Express each of the following in standard form.
(a) 376510
(b) 47865400
(c) 0.000507
(d) 0.00006408

Solution:
(a) 3.7651 × 105
(b) 4.78654 × 107
(c) 5.07 × 10-4
(d) 6.408 × 10-5

Question 4:
1.3 × 1015 + 3.2 × 1014

Solution:
1.3 × 1015 + 3.2 × 1014
= 1.3 × 1015 + 0.32 × 1015
= (1.3 +0. 32) × 1015
= 1.62 × 1015

Question 5:
0.0000036 – 2.1 × 10-7

Solution:
0.0000036 – 2.1 × 10-7
= 3.6 × 10-6 – 2.1 × 10-7
= 3.6 × 10-6 – 0.21 × 10-6
= (3.6 - 0.21) × 10-6
= 3.39 × 10-6